Dr Cheng was born in Hong Kong. He graduated from the Salesian English School where he was awarded many academic prizes. He left Hong Kong in 1976 and studied in the UK. Dr Cheng received his BSc degree in physics and computer science and his PhD from King's College London (formerly Queen Elizabeth College), University of London in 1979 and 1982 respectively. He was awarded the Dillion Prize, a Britt Junior Scholarship and the University of London Scholarship. From 1982 to 1984, he was employed as a Research Fellow at King's College, London.

In September 1984, he was Principal Engineer for ERA Technology Ltd., an independent research and consultancy organization in electrical and electronic engineering in Leatherhead, UK, and he participated in the Falkland Mine Clearance Field Trial. From August 1987, Dr Cheng was Project Manager and Senior Consultant of Logica Space and Defence Systems Ltd., UK, and was in charge of a number of secret military research and pre-production projects in surveillance areas and on developing systems with NATO codification.

He joined City University of Hong Kong as a Senior Lecturer in September 1989 and is now Associate Professor. He received a Teaching Excellence Award from City University of Hong Kong in 1994/5 and an Excellent Paper Award from CAST Young Scientist Conference in 1995. He has published over 100 technical papers in journals and conference proceedings and has 4 Patents (USA, UK, China and RSA), 5 patent applications (USA, China), and over 20 classified publications. He received an Innovator Award by EDN Asia Magazine in January 1997. He received a certificate of merit in the Second Applied Research Excellence Awards 1998 at the City University of Hong Kong and a certificate of merit in the Chinese International Invention Expo 1998. He has been a Visiting Professor of Xiamen University and a Consultant Professor at Southern China Technology University. He was also an External Examiner of the Open University of Hong Kong (1993-99) and the Technical College (Tsing Yi, 1997 and Shatin 2001-). He is the Managing Director of MACAPS International Limited, a subsidiary of CityU Enterprises Ltd, and a non-executive director of Integrated Silicon Solution, Inc. He is also Director of the Smart Card Design Centre, an Innovated Technology Commission funded project. His biographical data was included in the 15^thedition of Who's Who in the World.

Dr Cheng is quite active in professional activities. He has been serving the IEE Hong Kong Executive Committee for over 7 years. He was the past Honorary Secretary (1993/94) and Chairman (94/95) of the Executive Committee. He has been a member and co-chairmen of a number of conferences organized locally and overseas. Currently, he is a member of the Training Accreditation Committee of IEE. He was the Vice President (1996-8), Assistant Honorary Secretary (1995-7) and is a Council Member (1995-2001) of the Hong Kong Association of Advancement of Science and Technology.